Does the current World Health Organization classification predict the outcome better in patients with noninvasive bladder cancer of early or regular onset?

Abstract

To compare the clinical outcome and prognostic power of the former and current World Health Organization (WHO) grading system in patients with early vs regular onset of noninvasive urothelial bladder cancer (UBC), as little is known of the natural history of early onset UBC and in how far it is reflected by histopathological grading and staging in guiding clinical decisions. The medical records of 69 consecutive patients presenting with initial UBC of early onset (>or=45 years old, EO) and of 100 randomly chosen patients with regular onset (RO) were reviewed. There were no significant differences in gender distribution, risk factors or tumour stage. All histopathological specimens were re-staged and re-graded according to the former and current WHO grading. In all, 51 EO and 63 RO patients with tumours staged pTa and complete follow-up information were analysed. Recurrence-free survival (RFS) was prolonged in patients with EO. In EO neither the former nor the current WHO grading system was significantly related to RFS or to progression to muscle-invasive disease. In RO, while both WHO grading systems were significantly related to RFS, only the current WHO grading system was related to progression. While larger studies are needed, UBC in patients with EO and RO do not seem to differ in risk factors and oncological outcome. The current WHO classification reflects the outcome more accurately than the former classification in patients with RO. However, for EO no grading system has sufficient prognostic power and novel methods, i.e. molecular markers, need to be evaluated for clinical use.